Metamorphic Buffer Layer Growth for Bulk InAs(x)Sb(1-x) LWIR Detectors

For the last few decades, there has been great activity aimed at developing III-V based alternatives to HgCdTe for LWIR detection. The goals include improved cost, uniformity, size/weight/power consumption, and performance. This III-V detector activity includes both materials advances and device design. Based on recent developments, there appears to be an excellent opportunity for a breakthrough in LWIR detectors using bulk InAsSb for LWIR nBn detectors. The first step in realizing high performance InAsSb LWIR nBn detectors is the development of a metamorphic buffer layer (MBL) for the epitaxial growth of high quality LWIR InAsSb. At present there are several approaches for developing MBLs and, at the moment, it is not clear which approach is best. This Phase I program brings together MOVPE and MBE growth teams and capabilities, together with a III-V wafer merchant suppler, which will experimentally evaluate the various MBL approaches for LWIR InAsSb, and determine which MBL approach produces the best quality InAsSb for LWIR detectors. Phase II will implement this preferred MBL approach for construction of high performance LWIR InAsSb nBn focal plane arrays.